The Research Of Anti-Titin Antibody In Patients With Myasthenia Gravis

Objective To measure the serum level of anti-titin antibody in MG patients and analyze its relation with age, sex, clinical types, different thymic pathological patterns and prognosis of MG patientsMethods We had examined the level of anti-titin antibody with enzyme-linked immunosorbentassay (ELISA) using recombinant MGT-30 of purified fragment of titin as antigen, in the sera of 80 cases of MG (among them,22 with thymoma,47 with thymic hyperplasia,3 with thymic atrophy,8 with nomal thymic),30 cases of other neurologieal diseases (ONDs) and 30 cases of health control groups. In addition, we compared the levels of anti-titin antibody before and after thymectomy treatment in 54 cases MG patients.Results Serum anti-titin antibody could be detected in 42.5% of patients with MG, while the positive rate of anti-titin antibody was 3.3% in ONDs group and it was negative in health control group. And in children, young adult and aged patients, the positive rates were 9.1%,38.2%,85.7%, respectively. About 77.80% in late-onset MG group (more than 50 years old and without thymoma) and 77.3% in MG with thymoma (MGT) could be detected anti-titin antibody. It was 45.8%, 43.7% in male group and female group. So the positive rate of anti-titin antibody in MG group was significantly higher than that in ONDs and health control groups. And with the age, the level of anti-titin antibody also increased gradually, but there were cosignificant changes in male and female patients.The positive rates of anti-titin antibody in MG patients with different thymic pathological patterns (type A, AB and B thymoma) were 33.3%,80% and 85.7%, respectively. And there were no significant differencres among them, but changes of anti-titin antibody level were obvious in sera of 54 MG patients before and after operation (P<0.05). Conclusions:Positive anti-titin antibody is mostly found in late-onset MG, MGT, especially in Type B, The positive rate of anti-titin antibody had no correlation with sex,, but had a significant correlation with the disease severity. Serum anti-titin antibody test can be taken as reference index in the diagnosis of MG, especially to MGT. It might be beneficial for evaluating prognosis of MG patients after operation.